A nationalization isn't so bad if there's a reason for it and the company is run well. The state can run public utilities, roads, and other things very well. Maybe even oil isn't too much.
But the problem with government control of superfluous aspects of the economy is that it usually doesn't care whether or not they do well or turn a profit. Even if the cement industry is performing poorly now, the government isn't going to cut back. That would be unpopular. So basically, there's at least nothing good that can come about from this.
